Design, BSA Binding, Stopped-Flow Kinetic, Mechanistic, Molecular Docking, and Biological Evaluation of Hy-droxychloroquine-Based Chitosan Nanoparticles for Enhancing Anticancer Activity in A549 Lung Cancer Cell Line

Abstract

The current study describes the preparation of chitosan nanoparticles (CNPs) using hydroxychloroquine (HCQ), widely used in traditional medicine due to its diverse phar-macological and medicinal uses. This work aims to combine the HCQ drug with CS NPs to generate a novel nanocomposite with improved characteristics and bioavailability. HCQ@CS NPs is roughly shaped like roadways and has a smooth surface with an average size of 159.3±7.1 nm, a PdI of 0.224±0.101, and a zeta potential of +46.6±0.8 mV. To aid in the development of pharmaceutical systems for use in cancer therapy, the binding mech-anism and affinity of the interaction between HCQ and HCQ@CS NPs and BSA were ex-amined using stopped-flow, other spectroscopic approaches, supplemented by molecular docking analysis. HCQ and HCQ@CS NPs binding with BSA is driven by a ground-state complex formation that may be accompanied by a non-radiative energy transfer process, and binding constants indicated that HCQ@CS NPs-BSA was more stable than HCQ-BSA. The stopped-flow analysis demonstrated that, in addition to increasing BSA affinity, the nano formulation HCQ@CS NPS changes the binding process and may open up new routes for interaction. Docking experiments verified the development of the HCQ-BSA complex, with HCQ binding to the site I on the BSA structure, primarily with the amino acids Thr 578, Gln 579, Gln 525, Tyr 400, and Asn 404. Furthermore, the nano-formulation HCQ@CS NPS not only increased cytotoxicity against the A549 lung cancer cell line (IC50 = 28.57±1.72 g/ml) compared to HCQ (102.21±0.67) g/ml), but also exhibited higher anti-bacterial activity against both Gram-positive and Gram-negative bacteria when compared to HCQ and chloramphenicol which in agreement with the binding constants. The nano formulation developed in this study may offer a viable therapy option for A549 lung cancer.